Track lighting systems and fixtures are used both in private houses and in public buildings, such as museums and commercial establishments, to provide ample illumination by the use of attractive components that blend well into the surrounding room design and decor. A conventional track lighting system includes a lighting track mounted to or in a ceiling. The lighting track typically includes a pair of buss bars consisting of a neutral line and a hot or voltage line. A lamp carried within a suitable socket is electrically connected to the buss bars and is mechanically secured to the lighting track by means of a fixture adapter from which the lamp socket extends downwardly from the lighting track and ceiling. Track lighting fixtures of this general type are described in, for example, U.S. Pat. Nos. 4,919,625 and 5,334,037.
In order to achieve a more pleasing appearance of a track lighting fixture, it is desirable for the fixture adapter to lie as flush as possible with the face or entry side of the lighting track section. Currently available fixture adapters, however, project by a perceptible distance below the face of the track section.
The currently available fixture adapters are generally difficult to install and to remove. A further difficulty that has been experienced with the known track lighting fixtures is that the force needed to remove the adapter from the lighting track is often sufficiently great to cause damage to the track mounting surface such as by loosening or bending the track supports in the ceiling or by digging into the ceiling surface. Moreover, in some of the currently available track lighting fixtures, replacing a lighting fixture may create safety problems.
In order to achieve optimum light orientation and distribution from a track lighting fixture, the lighting fixture is often aimed, that is, moved horizontally and vertically to a desired orientation. Aiming of the fixture is typically done when it is first installed and when it is located or aimed. In most conventional track lighting fixtures, it is difficult to lock and maintain the lighting fixture in the desired orientation after it has been aimed. Those track lighting fixtures that do permit the aimed fixture to be readily locked in a desired orientation are usually single-function operations, which often make it more difficult to achieve the desired orientation of the lighting fixture.
In order to create a variety of possible lighting effects, media accessories such as colored filters and diffusion filters and louvers and lenses of different sizes are often attached onto the lighting fixture by means of springs or other types of accessory holding devices. These devices are sometimes cumbersome and often do not permit several lighting media accessories to be used in conjunction with one another to provide a desired lighting effect.